Method for authenticating an electronic signature

ABSTRACT

A method for determining whether a disputed electronic signature is that of a purported signator includes the steps of (a) creating in a single step an ink on paper signature and an identical electronic signature of the purported signator; (b) verifying that the ink on paper signature is consistent with known ink on paper signatures of the purported signator; and (c) comparing the disputed electronic signature with the electronic signature of the purported signator to determine whether the disputed electronic signature is that of the purported signator.

FIELD OF THE INVENTION

This invention relates generally to methods for authenticatingsignatures and, more specifically, to methods for authenticatingelectronic signatures.

BACKGROUND OF THE INVENTION

Electronic (digitized) signatures are becoming increasingly common inthe execution of contracts, the payment for commercial transactions, andin many other aspects of commerce. A necessary component for the utilityand acceptance of electronic signatures is the ability to authenticatesuch signatures. Many such authentication procedures have been proposed,such as that disclosed in U.S. Pat. No. 6,307,955, the entirety of whichis incorporated by this reference.

All known prior art authentication methods, however, required theexistence of an established reference signature in electronic form.There are many circumstances, however, where such established referencesignatures in electronic form is not available and is no longerobtainable. Accordingly, there is a need for a method for verifying anelectronic signature where a verified signature may not be available.

SUMMARY

The invention satisfies this need. The invention is a method fordetermining whether a disputed electronic signature is that of apurported signator. The method comprises the steps of (a) creating in asingle step an ink on paper signature and an identical electronicsignature of the purported signator; (b) verifying that the ink on papersignature is consistent with known ink on paper signatures of thepurported signator; and (c) comparing the disputed electronic signaturewith the electronic signature of the purported signator to determinewhether the disputed electronic signature is that of the purportedsignator.

DETAILED DESCRIPTION

The following discussion describes in detail one embodiment of theinvention and several variations of that embodiment. This discussionshould not be construed, however, as limiting the invention to thoseparticular embodiments. Practitioners skilled in the art will recognizenumerous other embodiments as well.

The invention is a method for determining whether a disputed electronicsignature is that of a purported signator. The method comprises thesteps of (a) creating in a single step an ink on paper signature and anidentical electronic signature of the purported signator; (b) verifyingthat the ink on paper signature is consistent with known ink on papersignatures of the purported signator; and (c) comparing the disputedelectronic signature with the electronic signature of the purportedsignator to determine whether the disputed electronic signature is thatof the purported signator.

The creation of an ink-on-paper signature and an identical electronicsignature of the purported signator can be accomplished in many ways. Inone way, a piece of ordinary paper is placed over a touch sensitive padconnected to a computer. The signator signs his or her name with anordinary ink pen writing on the paper. An electronic signature issimultaneously obtained via the pressure of the ink pen against thetouch sensitive pad. Another way of creating an ink-on-paper signatureand an identical electronic signature is with an electronic pen having abuilt-in ink cartridge. A piece of ordinary paper is placed onto anactive area of an electronic pen tablet. Software within the computer isadapted to capture the signature data from the tablet while the inkcartridge within the electronic pen yields an ink-on-paper signature.

The electronic signature can also be obtained with an electronic penwhich reads microscopic coordinates on paper or one that senses positionwithout the need of a corresponding tablet, such as by using infraredsensors or other kind of pen tip sensing.

In one example of the invention, the method of the invention is used todetermine whether a disputed signature is that of an alleged signator.The creation of an ink-on-paper signature and an identical electronicsignature is carried out in the presence of a neutral third party, suchas a mediator in a mediation proceeding, a court reporter in a pre-trialdiscovery proceeding or a judge in a litigation proceeding. Theink-on-paper signature is then compared to known ink-on-paper signaturesof the alleged signator by a handwriting specialist using knownhandwriting forensic techniques. Once the ink-on-paper signature isconfirmed to be consistent with known ink-on-paper signatures of thealleged signator, the disputed electronic signature is compared with theelectronic signature prepared in step (a) by known comparison techniquesto determine whether the disputed electronic signature is that of thealleged signator.

The method of the invention has the additional advantage in thissituation that, if the alleged signator attempts to disguise his or hersignature during the creation of the ink-on-paper signature and anidentical electronic signature in step (a), this fact will be determinedin step (b) when the ink-on-paper signature prepared in step (a) isfound to be inconsistent with known ink-on-paper signatures of thealleged signator.

In another example of the invention, the signer of an electronicsignature in a commercial transaction or in the execution of a legaldocument, such as a will. The signator is asked at the time of executionto prepare, in a separate step, an ink-on-paper signature and anidentical electronic signature in step (a). Both the ink-on-papersignature and the identical electronic signature prepared in step (a)are retained in a file. Thereafter, when and if the authenticity of theelectronic signature on the commercial transaction or legal document isquestioned, the ink-on-paper and the identical electronic signatureprepared in step (a) is extracted from the file. The ink-on-papersignature is compared to known ink-on-paper signatures to verify thatthe ink-on-paper is that of the purported signator.

Having thus described the invention, it should be apparent that numerousstructural modifications and adaptations may be resorted to withoutdeparting from the scope and fair meaning of the instant invention asset forth hereinabove and as described hereinbelow by the claims.

1. A method of verifying whether a disputed electronic signature is thatof a signator, comprising the steps of: (a) obtaining a first ink onpaper signature from the signator for reference; (b) obtaining a firstelectronic signature in connection with a transaction; (c) obtaining, ina single step, a second ink on paper signature and a second electronicsignature from an individual, wherein the second ink on paper signatureand the second electronic signature are identical; (d) comparing thefirst ink on paper signature with the second ink on paper signature todetermine whether the first ink on paper signature is consistent withthe second ink on paper signature and thereby verify whether theindividual is the signator; and (e) comparing the first electronicsignature with the second electronic signature to determine whether thefirst electronic signature is consistent with the second electronicsignature and thereby verify whether the individual is the author of thefirst electronic signature.
 2. The method of claim 1, wherein the firstink on paper signature is consistent with the second ink on papersignature and the individual is confirmed to be the signator.
 3. Themethod of claim 1, wherein the first ink on paper signature is notconsistent with the second ink on paper signature and the individual isconfirmed not to be the signator.
 4. The method of claim 1, wherein thefirst electronic signature is consistent with the second electronicsignature and the individual is confirmed to be the author of the firstelectronic signature.
 5. The method of claim 1, wherein the firstelectronic signature is not consistent with the second electronicsignature and the individual is confirmed not to be the author of thefirst electronic signature.
 6. The method of claim 1, wherein thetransaction is a commercial transaction.
 7. The method of claim 1,wherein the transaction is a legal transaction.
 8. The method of claim1, wherein the transaction comprises the execution of a will.
 9. Amethod of verifying whether a first electronic signature obtained inconnection with a transaction is that of a signator, comprising thesteps of: (a) obtaining a first ink on paper signature from the signatorfor reference; (b) obtaining, in a single step, a second ink on papersignature and a second electronic signature from an individual, whereinthe second ink on paper signature and the second electronic signatureare identical; (c) comparing the first ink on paper signature with thesecond ink on paper signature to determine whether the first ink onpaper signature is consistent with the second ink on paper signature andthereby verify whether the individual is the signator; and (d) comparingthe first electronic signature with the second electronic signature todetermine whether the first electronic signature is consistent with thesecond electronic signature and thereby verify whether the individual isthe author of the first electronic signature.
 10. A method of verifyingwhether a disputed electronic signature is that of a signator,comprising the steps of: (a) obtaining a first electronic signature inconnection with a transaction, the first electronic signature being thedisputed electronic signature; (b) obtaining a first ink on papersignature from the signator for reference; (c) obtaining, in a singlestep, a second ink on paper signature and a second electronic signaturefrom an individual, wherein the second ink on paper signature and thesecond electronic signature are identical; (d) comparing the first inkon paper signature with the second ink on paper signature to determinewhether the first ink on paper signature is consistent with the secondink on paper signature and thereby verify whether the individual is thesignator; and (e) comparing the first electronic signature with thesecond electronic signature to determine whether the first electronicsignature is consistent with the second electronic signature and therebyverify whether the individual is the author of the first electronicsignature.